I just really love the idea of Newt being comfortable in Graves' presence, even when some others are scared of him. With his position and powerful magic, he can be freaking terrifying, but Newt relaxes when he's around Percival.

I don't really have a specific scenario in mind, so do what you will!

Bonus:
+At some point Newt is like "oh thank god it's you" and maybe all the other aurors are like "excuse you, he's scary as hell"